So
Sodium Stearate
Sodium Stearate
The sodium salt of stearic acid: a soap that cleanses and thickens.
What it does
Stearic acid is a fatty acid. Products use it to cleanse, to help oil and water mix and to thicken.
The evidence, graded
expert consensusUS safety reviewers (2019) assessed 102 fatty acids and their salts, used mostly to stop caking, steady mixtures or thicken. Their list names behenic, arachidic and isostearic acid and magnesium, sodium and aluminum stearate. Behenic acid is used at up to 14% in lipstick, magnesium stearate at up to 7.2% in face powders. Some can irritate skin, and the less stable fatty acids can break down into compounds that cause allergy. So products must be made not to irritate or cause allergy.Burnett 2019 · Cosmetic Ingredient Review ↗
Graded per the methodology: strong · moderate · emerging · expert consensus. A weak source on a strong claim gets the weaker label.
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